US3944606A - Process of producing alkali metal or ammonium citrates - Google Patents

Process of producing alkali metal or ammonium citrates Download PDF

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Publication number
US3944606A
US3944606A US05/518,714 US51871474A US3944606A US 3944606 A US3944606 A US 3944606A US 51871474 A US51871474 A US 51871474A US 3944606 A US3944606 A US 3944606A
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Prior art keywords
citric acid
alkali metal
amine
extraction
proportion
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Expired - Lifetime
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US05/518,714
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English (en)
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Manfred Rieger
Johannes Kioustelidis
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Joh A Benckiser GmbH
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Joh A Benckiser GmbH
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Priority claimed from DE19732355059 external-priority patent/DE2355059C3/de
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    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
    • C12P7/00—Preparation of oxygen-containing organic compounds
    • C12P7/40—Preparation of oxygen-containing organic compounds containing a carboxyl group including Peroxycarboxylic acids
    • C12P7/44—Polycarboxylic acids
    • C12P7/48—Tricarboxylic acids, e.g. citric acid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D11/00—Solvent extraction
    • B01D11/04—Solvent extraction of solutions which are liquid
    • B01D11/0488—Flow sheets
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/41—Preparation of salts of carboxylic acids
    • C07C51/412—Preparation of salts of carboxylic acids by conversion of the acids, their salts, esters or anhydrides with the same carboxylic acid part

Definitions

  • the present invention relates to a process of producing citrates and more particularly to the process of producing -- by means of extraction -- alkali metal or ammonium citrates from citric acid solutions produced by chemical methods or by fermentation.
  • Alkali metal citrates have also been produced by directly neutralizing citric acid solutions. In this case, however, it is necessary to employ citric acid solutions in a substantially pure form. Both known methods are complicated and require many expensive and time consuming process steps.
  • Butanol-2 is used as extracting agent according to French Pat. No. 1,211,066, while German Published application No. 1,268,088 employs tri-n-butyl phosphate in mixture with hydrocarbons, ethers, esters, or ketones for this purpose.
  • German Published application No. 1,268,088 employs tri-n-butyl phosphate in mixture with hydrocarbons, ethers, esters, or ketones for this purpose.
  • it was not possible to obtain satisfactory results with these known methods of extraction because the distribution coefficient in both described extraction processes is so low (about 1.0) that large amounts of the extracting agents and many extraction steps were required.
  • Another object of the present invention is to provide alkali metal citrates or ammonium citrates of a high degree of purity.
  • a further object of the present invention is to provide a mixture of extracting agents for carrying out the process of the present invention.
  • a specific extracting agent which is composed of a water-immiscible mixture of an amine of the following formula ##EQU1## in which R 1 and R 2 are aliphatic hydrocarbon radicals, preferably alkyl with 7 to 15 carbon atoms and
  • R 3 is hydrogen or an aliphatic hydrocarbon radical, preferably alkyl with 1 to 15 carbon atoms
  • the resulting extract is subsequently treated with alkali metal hydroxide, alkali metal carbonates or bicarbonates, ammonia, or salts thereof.
  • the alkali metal citrates are obtained in an excellent yield and are of a high degree of purity after the organic citric acid extract is re-extracted with the alkaline solutions.
  • the process according to the present invention has the further advantage that it is possible not only to produce trisodium citrate as it is obtained in the known reaction of calcium citrate with alkali metal carbonates, but also, depending upon the amount of the alkali metal compound used for re-extraction, to produce acid alkali metal citrate solutions.
  • This advantage is of special importance when recovering citric acid from the alkali metal citrate solutions by means of electrodialysis. Trisodium citrate solutions are less useful for electrodialytic recovery of citric acid because their pH-value is relatively high.
  • Suitable amines according to the present invention are, for instance, N-lauryl-N-trialkylmethylamine such as a mixture of secondary amines whereby the sum of alkyl carbon atoms varies between 11 and 14 carbon atoms, N-methyl-di-n-octylamine, tri-isononylamine, or tri-n-decylamine.
  • N-lauryl-N-trialkylmethylamine such as a mixture of secondary amines whereby the sum of alkyl carbon atoms varies between 11 and 14 carbon atoms
  • N-methyl-di-n-octylamine tri-isononylamine
  • tri-n-decylamine tri-n-decylamine
  • Suitable organic solvents according to the present invention are solvents which are not miscible with water but which have a high dissolving power for the system amine-citric acid. Hydrocarbons, alcohols, esters, ketones, or mixtures thereof can be employed as solvents. Suitable solvents, for instance, are
  • aliphatic and alicyclic hydrocarbons such as cyclohexene, dl-limonene, or
  • halogenated hydrocarbons such as carbon tetrachloride
  • aliphatic alcohols with 5 to 10 carbon atoms such as methyl isobutyl carbinol, 2-methyl-5-hexanol, 1-octanol, 2-ethyl-1-hexanol, or
  • aromatic alcohols and phenols such as benzylalcohol, phenol, preferably as carbolxylene, i.e. an about 9% solution of phenol in xylene;
  • aliphatic ketones such as methyl isobutyl ketone, 2-pentanone, 2-octanone, 5-methyl-3-heptanone, 2,6-dimethyl heptanone,
  • d. esters such as cyclohexylacetate or tri-n-butyl phosphate
  • the optimum proportion by volume of amine to organic solvent is within the range of about 0.05 to about 2.0 and preferably between about 0.3 to about 0.7 and the molar proportion of amine to citric acid is between about 0.5 to about 10.0 and preferably between about 1.5 and about 3.5.
  • the extracting solvents are preferably used in the proportion by volume of tri-isononylamine to methyl isobutyl ketone 1 : 1.5 corresponding to a v-value of 0.66 and in the molar proportion of amine to citric acid of 2 : 1, i.e. corresponding to an m-value of 2.0.
  • Table 1 shows the dependence of the distribution coefficient upon the v- and m-values.
  • the extraction of citric acid from the fermentation solution was carried out at 20° C.
  • Tri-isononylamine or, respectively, a mixture of tri-n-octylamine and tri-n-decylamine were used as amines and methyl isobutyl ketone or, respectively, methyl isobutyl carbinol as solvents.
  • Extraction as well as re-extraction can be carried out discontinuously, i.e. in batch operation or, respectively, continuously, for instance, by means of a battery of mixing and separating vessels or by means of an extraction column.
  • the organic extract is subsequently reacted with alkali metal hydroxides, ammonia, or their salts, such as the carbonates, chlorides, sulfates, or phosphates.
  • alkali metal sulfates or phosphates are preferably used as re-extracting agents when the resulting citrates are to be employed in detergents.
  • Alkali metal hydroxides, carbonates, bicarbonates, or salts are the preferred re-extracting agents although the corresponding ammonium compounds may also be used.
  • Acid citrate solutions can be produced from the organic extracts by extracting the citric acid not only with sodium carbonate and other alkali metal or ammonium carbonates or bicarbonates but also with alkali metal hydroxides or ammonia with a high distribution coefficient.
  • concentration values are determined by the solubility of the re-extracting agent in water as well as by the solubility of alkali metal or ammonium citrates in the resulting extract at re-extraction temperature.
  • concentration values are also dependent on the optimum proportion by volume of the aqueous phase, i.e. the re-extracting agent to the organic phase.
  • the alkali metal or ammonium citrate solution obtained according to the present invention can be concentrated in order to produce the solid salts. Such concentration is carried out in a manner known per se.
  • the solid salts find extensive use, for instamce, as substitutes for phosphates in detergents.
  • FIG. 1 shows, illustrated in graphs, the dependence of the distribution coefficient, free citric acid and the pH-value of the aqueous re-extraction solution from the a-value, while
  • FIG. 2 illustrates diagrammatically the process according to the present invention with three extraction steps and two re-extraction steps.
  • FIG. 1 graphically illustrates the interdependence of the distribution coefficient K, the free citric acid H in weight percent of total citric acid, and the pH-value of the aqueous re-extraction solution from the avalue, i.e. the equivalent proportion of sodium carbonate to citric acid when using sodium carbonate solutions as re-extracting solvent.
  • the one ordinate shows the proportion of free citric acid to total citric acid in weight percent, designated as H and the distribution coefficient K, and the other ordinate the pH-value.
  • the abscissa a shows the proportion of sodium carbonate to citric acid, i.e. the equivalent proportions of these two agents.
  • a fermentation solution containing 79 g. of citric acid in each liter of solution is subjected to continuous counterflow extraction in the mixing and separating system as diagrammatically illustrated in FIG. 2, which shows a three-step extraction and a two-step re-extraction process.
  • FIG. 2 shows a three-step extraction and a two-step re-extraction process.
  • a larger or smaller number of extraction and/or re-extraction steps may be used depending upon the extraction conditions.
  • the organic phase E1 drawn off from separator 2 is mixed with 12 l./hr. of the aqueous phase A1 in mixing vessel 3 and is then introduced into separator 4. Twelve l./hr. of aqueous phase A2 and 12 l./hr. of organic phase E2 are removed.
  • the organic phase E2 is mixed with the fermentation solution A0 containing 79 g. of citric acid per liter solution in mixing device 5 with a speed of 12 l./hr. Thereafter, the mixture is conducted to separator 6. 12 l./hr. of the organic extract E3 containing 76.2g. of citric acid per l. of extract are drawn off from separator 6 and are mixed in mixer 7 with 6 l. of aqueous phase W1 for re-extraction. The resulting mixture is then introduced into separator 8. 6 l. of the citrate solution W2 which contains 152.4 g./l. of citric acid or, calculated as trisodium citrate dihydrate, 233.4 g./l., and 12 l.
  • the citrate solution obtained according to the present invention has a degree of purity of 88 percent, i.e. 88 percent of the coloring matter in the starting fermentation solution have been removed.
  • E o is the extinction value of the starting solution (determined at a pH of 5.5; measuring cell: 1 cm.; wave length: 436 nm.)
  • C o is the amount of citric acid in 1 ml. of solution.
  • the amount of coloring matter in the citrate solution calculated for C g. of citric acid is
  • E e is the extinction value of the citrate solution (determined in the same manner as the extinction value of E o ) and
  • C e is the amount of citric acid in 1 ml. of citrate solution.
  • the purifying effect R is defined as follows: ##EQU2##
  • a fermentation solution containing 71.5 g./l. of citric acid is extracted by continuous counter-current extraction in the extraction mixer/separator system described in Example 1 and FIG. 2.
  • the organic phases and the aqueous phases are supplied for extraction to the mixers and separators with the same speed of 12 l./hr.
  • An about 0.3% aqueous phase (refined solution) is discharged from separator 2 while the organic extract of 68.3 g./l. of citric acid is drawn off from separator 6 and is fed into mixer 7.
  • a potassium hydroxide solution containing 162 g./l. of potassium hydroxide is used as re-extracting agent.
  • the resulting aqueous extract which is discharged from separator 8 contains 204.9 g/l. of citric acid or, calculated as tripotassium citrate monohydrate, 346.0 g./l.

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US05/518,714 1973-11-03 1974-10-29 Process of producing alkali metal or ammonium citrates Expired - Lifetime US3944606A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DT2355059 1973-11-03
DE19732355059 DE2355059C3 (de) 1973-11-03 Verfahren zur Gewinnung von Alkall- oder Ammoniumeitraten

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US (1) US3944606A (fr)
BE (1) BE821777A (fr)
FR (1) FR2249867B3 (fr)
GB (1) GB1447575A (fr)
IE (1) IE39950B1 (fr)
IT (1) IT1020235B (fr)
NL (1) NL7414124A (fr)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4275234A (en) * 1972-06-19 1981-06-23 Imi (Tami) Institute For Research And Development Recovery of acids from aqueous solutions
US4308398A (en) * 1980-08-04 1981-12-29 Miles Laboratories, Inc. Elimination of reducing sugars present in trisodium citrate
US4334095A (en) * 1980-10-06 1982-06-08 Miles Laboratories, Inc. Extraction of organic acids from aqueous solutions
US4444881A (en) * 1981-10-26 1984-04-24 Cpc International Inc. Recovery of organic acids from a fermentation broth
US4698303A (en) * 1985-02-15 1987-10-06 Engenics, Inc. Production of lactic acid by continuous fermentation using an inexpensive raw material and a simplified method of lactic acid purification
US4771001A (en) * 1986-03-27 1988-09-13 Neurex Corp. Production of lactic acid by continuous fermentation using an inexpensive raw material and a simplified method of lactic acid purification
EP0460854A1 (fr) * 1990-06-06 1991-12-11 Cargill, Incorporated Préparation de l'acide citrique
EP0432610A3 (en) * 1989-12-11 1992-03-18 Innova S.A. Concurrent production of citric acid and alkali citrates
US5162214A (en) * 1991-04-05 1992-11-10 General Atomics International Services Corporation Cma production utilizing acetate ion exchange from fermentation broth
US5231225A (en) * 1989-12-11 1993-07-27 Innova S.A. Concurrent production of citric acid and alkali citrates
US5237098A (en) * 1992-10-09 1993-08-17 Miles, Inc. Production of citric acid and trisodium citrate from molasses
US5352825A (en) * 1993-07-06 1994-10-04 Hoarmann & Reimer Corp. Recovery of organic acid salts from impure process streams by addition of bases
WO1995002716A1 (fr) * 1993-07-12 1995-01-26 Aharon Eyal Procede de production de sels hydrosolubles d'acides carboxyliques et amines
US5426219A (en) * 1993-07-26 1995-06-20 A.E. Staley Manufacturing Co. Process for recovering organic acids
US5426220A (en) * 1993-03-04 1995-06-20 Innova, S.A. Citric acid extraction
WO1996038433A1 (fr) * 1995-05-31 1996-12-05 Yissum Research Development Company Of The Hebrew University Of Jerusalem Procede et compositions pour la recuperation de l'acide ascorbique
US5766439A (en) * 1996-10-10 1998-06-16 A. E. Staley Manufacturing Co. Production and recovery of organic acids
US6022992A (en) * 1995-09-19 2000-02-08 Yissum Research Development Company Of The Hebrew University Of Jerusalem Acid-salt metathetic process
US6037480A (en) * 1995-05-31 2000-03-14 Yissum Research Development Company Of The Hebrew University Of Jerusalem Process and compositions for the recovery of ascorbic acid
US6153791A (en) * 1999-08-02 2000-11-28 Archer-Daniels-Midland Company Process for purifying 2-keto-L-gulonic acid
US6509179B1 (en) 2000-10-12 2003-01-21 Barbara I. Veldhuis-Stribos Continuous process for preparing lactic acid
US20040010040A1 (en) * 2001-07-30 2004-01-15 Dyck Stefaan Van Solid phase synthesis of salts of organic acids including butyric acid
US6986909B2 (en) 2001-07-30 2006-01-17 Kemin Industries, Inc. Solid phase synthesis of salts of organic acid

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB874030A (en) * 1958-10-01 1961-08-02 Melle Usines Sa Process for extracting citric acid from aqueous solutions thereof
GB905817A (en) * 1960-02-01 1962-09-12 Miles Lab Improvements in the purification of citric acid
US3904684A (en) * 1972-05-03 1975-09-09 Takeda Chemical Industries Ltd Method for producing sodium citrate dihydrate

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB874030A (en) * 1958-10-01 1961-08-02 Melle Usines Sa Process for extracting citric acid from aqueous solutions thereof
GB905817A (en) * 1960-02-01 1962-09-12 Miles Lab Improvements in the purification of citric acid
US3904684A (en) * 1972-05-03 1975-09-09 Takeda Chemical Industries Ltd Method for producing sodium citrate dihydrate

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4275234A (en) * 1972-06-19 1981-06-23 Imi (Tami) Institute For Research And Development Recovery of acids from aqueous solutions
US4308398A (en) * 1980-08-04 1981-12-29 Miles Laboratories, Inc. Elimination of reducing sugars present in trisodium citrate
US4334095A (en) * 1980-10-06 1982-06-08 Miles Laboratories, Inc. Extraction of organic acids from aqueous solutions
US4444881A (en) * 1981-10-26 1984-04-24 Cpc International Inc. Recovery of organic acids from a fermentation broth
US4698303A (en) * 1985-02-15 1987-10-06 Engenics, Inc. Production of lactic acid by continuous fermentation using an inexpensive raw material and a simplified method of lactic acid purification
US4771001A (en) * 1986-03-27 1988-09-13 Neurex Corp. Production of lactic acid by continuous fermentation using an inexpensive raw material and a simplified method of lactic acid purification
US5231225A (en) * 1989-12-11 1993-07-27 Innova S.A. Concurrent production of citric acid and alkali citrates
EP0432610A3 (en) * 1989-12-11 1992-03-18 Innova S.A. Concurrent production of citric acid and alkali citrates
EP0460854A1 (fr) * 1990-06-06 1991-12-11 Cargill, Incorporated Préparation de l'acide citrique
US5772890A (en) * 1991-04-05 1998-06-30 General Atomics International Services Corporation CMA production utilizing organic ion exchange from fermentation broth
US5162214A (en) * 1991-04-05 1992-11-10 General Atomics International Services Corporation Cma production utilizing acetate ion exchange from fermentation broth
EP0597235A1 (fr) * 1992-10-09 1994-05-18 HAARMANN & REIMER CORPORATOPN Préparation de l'acide citrique et de citrate trisodique à partir de mélasse
US5237098A (en) * 1992-10-09 1993-08-17 Miles, Inc. Production of citric acid and trisodium citrate from molasses
US5426220A (en) * 1993-03-04 1995-06-20 Innova, S.A. Citric acid extraction
US5352825A (en) * 1993-07-06 1994-10-04 Hoarmann & Reimer Corp. Recovery of organic acid salts from impure process streams by addition of bases
WO1995002716A1 (fr) * 1993-07-12 1995-01-26 Aharon Eyal Procede de production de sels hydrosolubles d'acides carboxyliques et amines
US5426219A (en) * 1993-07-26 1995-06-20 A.E. Staley Manufacturing Co. Process for recovering organic acids
WO1996038433A1 (fr) * 1995-05-31 1996-12-05 Yissum Research Development Company Of The Hebrew University Of Jerusalem Procede et compositions pour la recuperation de l'acide ascorbique
US6037480A (en) * 1995-05-31 2000-03-14 Yissum Research Development Company Of The Hebrew University Of Jerusalem Process and compositions for the recovery of ascorbic acid
US6022992A (en) * 1995-09-19 2000-02-08 Yissum Research Development Company Of The Hebrew University Of Jerusalem Acid-salt metathetic process
US5766439A (en) * 1996-10-10 1998-06-16 A. E. Staley Manufacturing Co. Production and recovery of organic acids
US6153791A (en) * 1999-08-02 2000-11-28 Archer-Daniels-Midland Company Process for purifying 2-keto-L-gulonic acid
US6509179B1 (en) 2000-10-12 2003-01-21 Barbara I. Veldhuis-Stribos Continuous process for preparing lactic acid
US20040010040A1 (en) * 2001-07-30 2004-01-15 Dyck Stefaan Van Solid phase synthesis of salts of organic acids including butyric acid
US6986909B2 (en) 2001-07-30 2006-01-17 Kemin Industries, Inc. Solid phase synthesis of salts of organic acid
US7001625B2 (en) 2001-07-30 2006-02-21 Kemin Industires, Inc. Solid phase synthesis of salts of organic acids including butyric acid

Also Published As

Publication number Publication date
IT1020235B (it) 1977-12-20
DE2355059A1 (de) 1975-05-07
FR2249867B3 (fr) 1977-08-05
IE39950L (en) 1975-05-03
DE2355059B2 (de) 1975-11-20
BE821777A (fr) 1975-02-17
NL7414124A (nl) 1975-05-07
IE39950B1 (en) 1979-01-31
GB1447575A (en) 1976-08-25
FR2249867A1 (fr) 1975-05-30

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